Hypotension is a common cause of syncope and falls in the elderly. Orthostatic hypotension and drug-induced hypotension are widely appreciated clinical problems; postprandial hypotension is a more recently recognized form of cardiovascular dysfunction in the aged. We intend to explore the role of gastrointestinal hormone secretion and neuropeptides in the pathophysiology of these disorders. The proposed studies are based upon our recent observation that somatostatin and a stomatostatin analogue, SMS-201-995, known inhibitors of gastrointestinal hormone secretion, raise the blood pressure in elderly patients with postprandial hypotension. The mechanism of this somatostatin effect is of considerable fundamental importance and its elucidation will further our understanding of hypotension in the elderly and the effect of aging on cardiovascular physiology. In addition, preliminary data indicate that the long-acting somatostatin analogue, SMS-201-995, holds considerable promise as a new form of therapy for hypotension which results from aging and autonomic dysfunction. This agent may be unique among the various drugs which have been advocated for the treatment of these disorders since preliminary indications suggest it reverses both postprandial and orthostatic hypotension.